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"Paras, Allan"
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Erratum: RSV-specific airway resident memory CD8+ T cells and differential disease severity after experimental human infection
by
Peters, Bjoern
,
Habibi, Maximillian S.
,
Kon, Onn Min
in
Erratum
,
Humanities and Social Sciences
,
multidisciplinary
2016
Nature Communications 6: Article number: 10224 (2015); Published: 21 December 2015; Updated: 9 March 2016 In Fig. 5 of this article, the three dot plots in the first row of panel a contain black numerical labels that are incorrect, and light blue labels that are correct. A revised version of Fig. 5,with correct labels in black throughout, appears below.
Journal Article
Impaired Antibody-Mediated Protection and Defective IgA B-Cell Memory in Experimental Infection of Adults with Respiratory Syncytial Virus
2015
Despite relative antigenic stability, respiratory syncytial virus (RSV) reinfects throughout life. After more than 40 years of research, no effective human vaccine exists and correlates of protection remain poorly defined. Most current vaccine candidates seek to induce high levels of RSV-specific serum neutralizing antibodies, which are associated with reduced RSV-related hospitalization rates in observational studies but may not actually prevent infection.
To characterize correlates of protection from infection and the generation of RSV-specific humoral memory to promote effective vaccine development.
We inoculated 61 healthy adults with live RSV and studied protection from infection by serum and mucosal antibody. We analyzed RSV-specific peripheral blood plasmablast and memory B-cell frequencies and antibody longevity.
Despite moderately high levels of preexisting serum antibody, 34 (56%) became infected, of whom 23 (68%) developed symptomatic colds. Prior RSV-specific nasal IgA correlated significantly more strongly with protection from polymerase chain reaction-confirmed infection than serum neutralizing antibody. Increases in virus-specific antibody titers were variable and transient in infected subjects but correlated with plasmablasts that peaked around Day 10. During convalescence, only IgG (and no IgA) RSV-specific memory B cells were detectable in peripheral blood. This contrasted with natural influenza infection, in which virus-specific IgA memory B cells were readily recovered.
This observed specific defect in IgA memory may partly explain the ability of RSV to cause recurrent symptomatic infections. If so, vaccines able to induce durable RSV-specific IgA responses may be more protective than those generating systemic antibody alone.
Journal Article
RSV-specific airway resident memory CD8+ T cells and differential disease severity after experimental human infection
2015
In animal models, resident memory CD8+ T (Trm) cells assist in respiratory virus elimination but their importance in man has not been determined. Here, using experimental human respiratory syncytial virus (RSV) infection, we investigate systemic and local virus-specific CD8+ T-cell responses in adult volunteers. Having defined the immunodominance hierarchy, we analyse phenotype and function longitudinally in blood and by serial bronchoscopy. Despite rapid clinical recovery, we note surprisingly extensive lower airway inflammation with persistent viral antigen and cellular infiltrates. Pulmonary virus-specific CD8+ T cells display a CD69+CD103+ Trm phenotype and accumulate to strikingly high frequencies into convalescence without continued proliferation. While these have a more highly differentiated phenotype, they express fewer cytotoxicity markers than in blood. Nevertheless, their abundance before infection correlates with reduced symptoms and viral load, implying that CD8+ Trm cells in the human lung can confer protection against severe respiratory viral disease when humoral immunity is overcome.
Respiratory syncytial virus (RSV) is a common cause of respiratory tract infections. Here the authors analyse cellular immune responses of individuals experimentally infected with RSV and reveal the presence of high frequencies of virus- specific resident memory CD8
+
T cells in the airway, which correlate with improved viral control.
Journal Article
Long-term safety and efficacy of patisiran for hereditary transthyretin-mediated amyloidosis with polyneuropathy: 12-month results of an open-label extension study
2021
Hereditary transthyretin-mediated amyloidosis is a rare, inherited, progressive disease caused by mutations in the transthyretin (TTR) gene. We assessed the safety and efficacy of long-term treatment with patisiran, an RNA interference therapeutic that inhibits TTR production, in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy.
This multicentre, open-label extension (OLE) trial enrolled patients at 43 hospitals or clinical centres in 19 countries as of Sept 24, 2018. Patients were eligible if they had completed the phase 3 APOLLO or phase 2 OLE parent studies and tolerated the study drug. Eligible patients from APOLLO (patisiran and placebo groups) and the phase 2 OLE (patisiran group) studies enrolled in this global OLE trial and received patisiran 0·3 mg/kg by intravenous infusion every 3 weeks with plans to continue to do so for up to 5 years. Efficacy assessments included measures of polyneuropathy (modified Neuropathy Impairment Score +7 [mNIS+7]), quality of life, autonomic symptoms, nutritional status, disability, ambulation status, motor function, and cardiac stress, with analysis by study groups (APOLLO-placebo, APOLLO-patisiran, phase 2 OLE patisiran) based on allocation in the parent trial. The global OLE is ongoing with no new enrolment, and current findings are based on the interim analysis of the patients who had completed 12-month efficacy assessments as of the data cutoff. Safety analyses included all patients who received one or more dose of patisiran up to the data cutoff. This study is registered with ClinicalTrials.gov, NCT02510261.
Between July 13, 2015, and Aug 21, 2017, of 212 eligible patients, 211 were enrolled: 137 patients from the APOLLO-patisiran group, 49 from the APOLLO-placebo group, and 25 from the phase 2 OLE patisiran group. At the data cutoff on Sept 24, 2018, 126 (92%) of 137 patients from the APOLLO-patisiran group, 38 (78%) of 49 from the APOLLO-placebo group, and 25 (100%) of 25 from the phase 2 OLE patisiran group had completed 12-month assessments. At 12 months, improvements in mNIS+7 with patisiran were sustained from parent study baseline with treatment in the global OLE (APOLLO-patisiran mean change –4·0, 95 % CI –7·7 to −0·3; phase 2 OLE patisiran –4·7, –11·9 to 2·4). Mean mNIS+7 score improved from global OLE enrolment in the APOLLO-placebo group (mean change from global OLE enrolment −1·4, 95% CI –6·2 to 3·5). Overall, 204 (97%) of 211 patients reported adverse events, 82 (39%) reported serious adverse events, and there were 23 (11%) deaths. Serious adverse events were more frequent in the APOLLO-placebo group (28 [57%] of 49) than in the APOLLO-patisiran (48 [35%] of 137) or phase 2 OLE patisiran (six [24%] of 25) groups. The most common treatment-related adverse event was mild or moderate infusion-related reactions. The frequency of deaths in the global OLE was higher in the APOLLO-placebo group (13 [27%] of 49), who had a higher disease burden than the APOLLO-patisiran (ten [7%] of 137) and phase 2 OLE patisiran (0 of 25) groups.
In this interim 12-month analysis of the ongoing global OLE study, patisiran appeared to maintain efficacy with an acceptable safety profile in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Continued long-term follow-up will be important for the overall assessment of safety and efficacy with patisiran.
Alnylam Pharmaceuticals.
Journal Article
Epitope-specific airway-resident CD4+ T cell dynamics during experimental human RSV infection
2020
BACKGROUNDRespiratory syncytial virus (RSV) is an important cause of acute pulmonary disease and one of the last remaining major infections of childhood for which there is no vaccine. CD4+ T cells play a key role in antiviral immunity, but they have been little studied in the human lung.METHODSHealthy adult volunteers were inoculated i.n. with RSV A Memphis 37. CD4+ T cells in blood and the lower airway were analyzed by flow cytometry and immunohistochemistry. Bronchial soluble mediators were measured using quantitative PCR and MesoScale Discovery. Epitope mapping was performed by IFN-γ ELISpot screening, confirmed by in vitro MHC binding.RESULTSActivated CD4+ T cell frequencies in bronchoalveolar lavage correlated strongly with local C-X-C motif chemokine 10 levels. Thirty-nine epitopes were identified, predominantly toward the 3' end of the viral genome. Five novel MHC II tetramers were made using an immunodominant EFYQSTCSAVSKGYL (F-EFY) epitope restricted to HLA-DR4, -DR9, and -DR11 (combined allelic frequency: 15% in Europeans) and G-DDF restricted to HLA-DPA1*01:03/DPB1*02:01 and -DPA1*01:03/DPB1*04:01 (allelic frequency: 55%). Tetramer labeling revealed enrichment of resident memory CD4+ T (Trm) cells in the lower airway; these Trm cells displayed progressive differentiation, downregulation of costimulatory molecules, and elevated CXCR3 expression as infection evolved.CONCLUSIONSHuman infection challenge provides a unique opportunity to study the breadth of specificity and dynamics of RSV-specific T-cell responses in the target organ, allowing the precise investigation of Trm recognizing novel viral antigens over time. The new tools that we describe enable precise tracking of RSV-specific CD4+ cells, potentially accelerating the development of effective vaccines.TRIAL REGISTRATIONClinicalTrials.gov NCT02755948.FUNDINGMedical Research Council, Wellcome Trust, National Institute for Health Research.
Journal Article
Detection of respiratory syncytial virus defective genomes in nasal secretions is associated with distinct clinical outcomes
2021
Respiratory syncytial virus (RSV) causes respiratory illness in children, immunosuppressed individuals and the elderly. However, the viral factors influencing the clinical outcome of RSV infections remain poorly defined. Defective viral genomes (DVGs) can suppress virus replication by competing for viral proteins and by stimulating antiviral immunity. We studied the association between detection of DVGs of the copy-back type and disease severity in three RSV A-confirmed cohorts. In hospitalized children, detection of DVGs in respiratory samples at or around the time of admission associated strongly with more severe disease, higher viral load and a stronger pro-inflammatory response. Interestingly, in experimentally infected adults, the presence of DVGs in respiratory secretions differentially associated with RSV disease severity depending on when DVGs were detected. Detection of DVGs early after infection associated with low viral loads and mild disease, whereas detection of DVGs late after infection, especially if DVGs were present for prolonged periods, associated with high viral loads and severe disease. Taken together, we demonstrate that the kinetics of DVG accumulation and duration could predict clinical outcome of RSV A infection in humans, and thus could be used as a prognostic tool to identify patients at risk of worse clinical disease.
Clinical outcomes of respiratory syncytial virus A infection are associated with kinetics of defective viral genome accumulation in humans.
Journal Article
Epitope-specific airway-resident CD4.sup.+ T cell dynamics during experimental human RSV infection
2020
BACKGROUND. Respiratory syncytial virus (RSV) is an important cause of acute pulmonary disease and one of the last remaining major infections of childhood for which there is no vaccine. [CD4.sup.+] T cells play a key role in antiviral immunity, but they have been little studied in the human lung. METHODS. Healthy adult volunteers were inoculated i.n. with RSV A Memphis 37. [CD4.sup.+] T cells in blood and the lower airway were analyzed by flow cytometry and immunohistochemistry. Bronchial soluble mediators were measured using quantitative PCR and MesoScale Discovery. Epitope mapping was performed by IFN-[gamma] ELISpot screening, confirmed by in vitro MHC binding. RESULTS. Activated [CD4.sup.+] T cell frequencies in bronchoalveolar lavage correlated strongly with local C-X-C motif chemokine 10 levels. Thirty-nine epitopes were identified, predominantly toward the 3' end of the viral genome. Five novel MHC II tetramers were made using an immunodominant EFYQSTCSAVSKGYL (F-EFY) epitope restricted to HLA-DR4, -DR9, and -DR11 (combined allelic frequency: 15% in Europeans) and G-DDF restricted to HLA-DPA1*01:03/DPB1*02:01 and -DPA1*01:03/DPB1*04:01 (allelic frequency: 55%). Tetramer labeling revealed enrichment of resident memory [CD4.sup.+] T (Trm) cells in the lower airway; these Trm cells displayed progressive differentiation, downregulation of costimulatory molecules, and elevated CXCR3 expression as infection evolved. CONCLUSIONS. Human infection challenge provides a unique opportunity to study the breadth of specificity and dynamics of RSV-specific T-cell responses in the target organ, allowing the precise investigation of Trm recognizing novel viral antigens over time. The new tools that we describe enable precise tracking of RSV-specific [CD4.sup.+] cells, potentially accelerating the development of effective vaccines. TRIAL REGISTRATION. ClinicalTrials.gov NCT02755948. FUNDING. Medical Research Council, Wellcome Trust, National Institute for Health Research.
Journal Article
In vivo tumor immune microenvironment phenotypes correlate with inflammation and vasculature to predict immunotherapy response
2022
Response to immunotherapies can be variable and unpredictable. Pathology-based phenotyping of tumors into ‘hot’ and ‘cold’ is static, relying solely on T-cell infiltration in single-time single-site biopsies, resulting in suboptimal treatment response prediction. Dynamic vascular events (tumor angiogenesis, leukocyte trafficking) within tumor immune microenvironment (TiME) also influence anti-tumor immunity and treatment response. Here, we report dynamic cellular-level TiME phenotyping in vivo that combines inflammation profiles with vascular features through non-invasive reflectance confocal microscopic imaging. In skin cancer patients, we demonstrate three main TiME phenotypes that correlate with gene and protein expression, and response to toll-like receptor agonist immune-therapy. Notably, phenotypes with high inflammation associate with immunostimulatory signatures and those with high vasculature with angiogenic and endothelial anergy signatures. Moreover, phenotypes with high inflammation and low vasculature demonstrate the best treatment response. This non-invasive in vivo phenotyping approach integrating dynamic vasculature with inflammation serves as a reliable predictor of response to topical immune-therapy in patients.
Standard assessment of immune infiltration of biopsies is not sufficient to accurately predict response to immunotherapy. Here, the authors show that reflectance confocal microscopy can be used to quantify dynamic vasculature and inflammatory features to better predict treatment response in skin cancers.
Journal Article
A randomised controlled trial to evaluate the clinical and cost-effectiveness of Stimulant compared with Non-stimulant medication for adults with Attention-deficit/hyperactivity disorder and a history of Psychosis or biPolar disordER: SNAPPER
2025
Background
Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder involving inattention, hyperactivity and impulsivity, which starts in childhood and frequently persists into adulthood. Stimulant and non-stimulant medication are the mainstay of treatment in adults. ADHD in adults is commonly comorbid in people with severe mental illness (SMI) such as bipolar disorder (bipolar) and psychosis. There is substantial uncertainty over the effectiveness of stimulant and non-stimulant medication in adult ADHD comorbid with SMI. There is also concern that they could trigger or worsen psychotic or manic symptoms. Whilst National Institute of Health and Care Evidence (NICE) ADHD guidelines indicate available evidence does not justify a deviation from their main recommendations of using stimulants first line, this is based on limited studies within this comorbid population. A randomised controlled trial (RCT) is needed to address this evidence gap. We present a protocol for a pragmatic, observer-blind, multi-centre, two-arm, RCT called SNAPPER that aims to investigate the clinical and cost-effectiveness of stimulant compared with non-stimulant medication for adults with ADHD and a history of SMI.
Methods
The recruitment target is 244 participants, aged 18 years or above, who have a history of SMI (either bipolar disorder or psychosis) with ADHD. Having provided informed consent for screening, participants will undergo validated diagnostic screening assessments to re-confirm the diagnosis of bipolar or psychosis and confirm an ADHD diagnosis. Those with confirmed diagnoses will provide informed consent for entry to the main trial and will then be randomised to receive either stimulant (lisdexamfetamine) or non-stimulant (atomoxetine) medication. The primary outcome measure is observer-rated ADHD symptom severity at 6 months. Secondary outcomes include ADHD symptom severity at 12 months, emergence of symptoms of bipolar or psychosis, health-related quality of life, occupational, daily functioning, substance misuse, cost-effectiveness, adherence, concomitant medication and process outcomes at 6 and 12 months.
Discussion
Given that untreated ADHD is associated with poor clinical outcomes, unemployment and criminal justice system involvement, clear evidence in this area is likely to improve recovery for individuals with ADHD and a history of SMI, reducing costs for the individual, the NHS and society.
Trial registration
ISRCTN79796233. Registered on 19/05/2022.
https://www.isrctn.com/ISRCTN79796233
.
Journal Article
Differential SLC6A4 methylation: a predictive epigenetic marker of adiposity from birth to adulthood
2019
BackgroundThe early life environment may influence susceptibility to obesity and metabolic disease in later life through epigenetic processes. SLC6A4 is an important mediator of serotonin bioavailability, and has a key role in energy balance. We tested the hypothesis that methylation of the SLC6A4 gene predicts adiposity across the life course.MethodsDNA methylation at 5 CpGs within the SLC6A4 gene identified from a previous methyl binding domain array was measured by pyrosequencing. We measured DNA methylation in umbilical cord (UC) from children in the Southampton Women’s Survey cohort (n = 680), in peripheral blood from adolescents in the Western Australian Pregnancy Cohort Study (n = 812), and in adipose tissue from lean and obese adults from the UK BIOCLAIMS cohort (n = 81). Real-time PCR was performed to assess whether there were corresponding alterations in gene expression in the adipose tissue.ResultsLower UC methylation of CpG5 was associated with higher total fat mass at 4 years (p = 0.031), total fat mass at 6–7 years (p = 0.0001) and % fat mass at 6–7 years (p = 0.004). Lower UC methylation of CpG5 was also associated with higher triceps skinfold thickness at birth (p = 0.013), 6 months (p = 0.038), 12 months (p = 0.062), 2 years (p = 0.0003), 3 years (p = 0.00004) and 6–7 years (p = 0.013). Higher maternal pregnancy weight gain (p = 0.046) and lower parity (p = 0.029) were both associated with lower SLC6A4 CpG5 methylation. In adolescents, lower methylation of CpG5 in peripheral blood was associated with greater concurrent measures of adiposity including BMI (p ≤ 0.001), waist circumference (p = 0.011), subcutaneous fat (p ≤ 0.001) and subscapular, abdominal and suprailiac skinfold thicknesses (p = 0.002, p = 0.008, p = 0.004, respectively). In adipose tissue, methylation of both SLC6A4 CpG5 (p = 0.019) and expression of SLC6A4 (p = 0.008) was lower in obese compared with lean adults.ConclusionsThese data suggest that altered methylation of CpG loci within SLC6A4 may provide a robust marker of adiposity across the life course.
Journal Article